European Agroforestry Conference: integrating science & policy to promote agroforestry practice (2nd). Book of Abstracts

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EURAF

EUROPEAN AGROFORESTRY FEDERATION

2 nd

European Agroforestry Conference

Integrating Science and Policy to Promote Agroforestry in Practice

Book of Abstracts

June 2014 Cottbus, Germany Editor-In-Chief: João HN Palma Editors: Anja Chalmin Paul Burgess Jo Smith Mike Strachan Jabier Ruiz Mirazo Adolfo Rosati Organizing Committee: Dirk Freese Anja Chalmin Christian Dupraz Rosa Mosquera-Losada Anastasia Panthera Norbert Lammersdorf João HN Palma Joana A Paulo Scientific Committee: Adolfo Rosati Anastasia Panthera Ansgar Quinkenstein Gerardo Moreno Jo Smith Joana A Paulo João HN Palma Rosa Mosquera-Losada Sami Kryeziu

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Preface

Who is afraid of agroforestry?

The European Agroforestry Federation is proud to bring to you the second European Agroforestry Conference, in Cottbus, Germany.

The first European Agroforestry Conference was held in Brussels in October 2012, and was landmarked by an unprecedented parallel session at the European Parliament. This was the first time European Members of the Parliament discussed this topic and listened to policy proposals formulated by EURAF. Not the last.... In the last two years, they had more opportunities to learn about agroforestry, as EURAF became more and more involved in Agroforestry lobbying, both at the European level and at the national levels in many European countries.

This second European Agroforestry Conference occurs at a special time : the time when the new Common Agricultural Policy (CAP) is being implemented across Europe for the next 6 years. This new CAP is more friendly to trees outside forest than ever. For the first time, a definition of agroforestry is included in an European policy. Thanks to EURAF and to the dedication of its members. The focus of this conference (how to integrate science and policy to promote agroforestry) is therefore crucial. Now that policy has taken agroforestry on board, scientist may feel under pressure. They are. But let’s share the pressure, lets exchange ideas, novels, concepts, results. Let’s document agroforestry failures as well as agroforestry successes.

Agroforestry is not an evidence. Agroforestry is not the solution to all the problems of modern agriculture. But agroforestry can be part of it.

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Brandenburg University of Technology Cottbus-Senftenberg

Brandenburg University of Technology is pleased to host the 2nd European Agroforestry Conference between 4th and 6th June 2014 entitled “Integrating Science & Policy to Promote Agroforestry in Practice”. Agroforestry had some traditions as an optional land use system in Central Europe, but during the last eighty years these management systems disappeared progressively due to the ongoing industrialization of agriculture and the resulting land consolidation.

The recent rising demand for woody biomass for bioenergy in Germany is expected to lead to an increased cultivation of trees on farmland. As a result, there are numerous research projects that deal with these current issues, e.g. agroforestry systems with short rotation components.

The Chair of Soil Protection and Recultivation at the Brandenburg University of Technology has been intensively engaged in the research field of agroforestry for more than 15 years. The background of this research remains to be in understanding how fast growing tree species planted in agroforestry systems, but also in short rotation coppices, affect abiotic and biotic functions of the environment. Positive effects have been shown for the overall soil quality, the microclimate and the biodiversity.

The interaction between trees on crops and their impact on soil characteristics is the main focus of research including studies of humus accumulation in soil, carbon sequestration and nutrient cycle. Moreover, numerous studies are dealing with the carbon allocation in woody biomass, and hence, address questions concerning site specific yields of woody biomass on agricultural land.

In this context, post-mining areas play a very important role. Furthermore, the development and assessment of suitable reclamation measurements by using fast growing tree species is part of several investigations. The majority of studies are integral parts of national or international collaborative research projects founded by ministries, public institutions as well as industrial partners.

For more information about research projects and publications please visit:

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Biophysical Interactions in the Alley Cropping System in

Saskatchewan

Issah G1, 3, Kimaro A A 2*, Kort J3, Knight D J1

*Corresponding author: a.kimaro@cgiar.org

1 - Department of Soil Science, University of Saskatchewan 51 Campus Drive, Saskatoon, SK S7N 5A8 Canada 2 - World Agroforestry Centre, ICRAF-Tanzania Programme, Dar-es-Salaam, Tanzania

3 - Agriculture and Agri-Food Canada, Agroforestry Development Centre P.O. Box 940 Indian Head, SK S0G 2K0

Introduction

Crop production in alley cropping systems and in other mixed-species systems is dependent on the net effects of facilitative and competitive interactions on availability of growth resources (moisture, nutrients, and light) to the crop and trees components of the system. Controlling these interactions can benefit producers through the increased system productivity associated with optimized yields crops and trees. Previous research in the Canadian Prairies has focused on biophysical interactions in shelterbelts. These studies have demonstrated that trees in the shelterbelt system ameliorate soil moisture and temperature by reducing wind speed and trapping snow; this in turn reduces evaporative and heat stress leading to increased yields of intercrops (Marchand and Masse, 2008; Kort et al. 2009). Unlike Eastern Canada and United States (US), there is inadequate information on the on tree-crop interactions under alley cropping systems in the Canadian Prairies. Studies in these areas indicate that nutrient recycling by trees through nitrogen (N)-fixation and litter and root turnover can enhance soil nutrients, especially N thereby reducing fertilizer inputs in the alleyways (Thevathasan and Gordon, 2004). Because of the reduced N inputs and highly efficient capture of nitrate leaching to sub-soils by tree roots, alley cropping systems also hold high promise to reduce N2O emissions and groundwater contamination

(Doughterty et al. 2009). When plant growth is not limited by water and nutrients, plant biomass production is directly related to the radiant energy up to species-specific saturation points. In the absence of these growth-limiting factors, shading acts as facilitative rather than a competitive effect

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was to evaluate the effects of distance from tree row, row orientation, and sampling depth on soil moisture, light and yield and nutrition of oats (Avena sativa L.) in the alleyways.

Materials and Methods

The experiment was conducted on a 9-year-old Manitoba maple alley cropping site with oats in the alleys. The site is located in the experimental farm of the Agroforestry Development Centre, Indian Head, Saskatchewan (SK). Tree rows were planted 11 m apart in the East-West orientation in 2004 and the trees were 3 m high at the time of conducting this experiment. The factorial experiment with three factors was laid out in randomized complete block (RCBD) with four replications to test the effects of: 1) orientation (north and south), 2) distance from the maple tree row (i.e. 2 m, 4 m and 6 m), and 3) soil depth (for soil parameters like moisture & nutrients) or time of day (for light parameters) on yields and nutrition of oats. Oats were seeded at 90 kg ha-1 in 2012 and sampled for dry matter and nutrient analysis at the tussling stage to coincide with the active growth stage. Oat samples were collected from a 60 cm × 60 cm quadrant at 2 m, 4 m and 6 m from the tree row in each orientation by cutting at 5 cm from the ground. Gravimetric soil moisture samples were collected from the same distance and orientations using a Dutch auger. Photosynthetically active radiation (PAR) was also measured in these locations three times per day (morning, solar noon and evening), on clear sunny days using a Sun Scan Canopy Analysis System. Prior to conducting statistical analysis normal distribution of residuals were confirmed by Shapiro-Wilk test in SAS. Analyses of soil moisture content (SMC) and PAR were done by the repeated measure approach while biomass and nutrient contents were analyzed using ANOVA provided in the PROC MIXED procedure. All analyses were conducted at 5% probability level and significant means were compared using Tukey’s Honestly Significant Difference (HSD).

Results

SMC declined significantly (p ˂ .0001) with sampling depth and plot orientation, but no differences were noted due to distance from the tree-row (Fig. 1). SMC was however comparatively higher in the northern compared to the southern orientation and it was lower at 2 m than at 4 m and 6 m from the tree row in the southern orientation. PRA ranged from 400 to 1.000 μmol m−2 s−1and was the lowest (p ˂ .0001) at 2 m in the north facing plots. At noon, PAR in the southern orientation (p ˂ .0001) was higher than in northern orientation (Fig. 2; p ˂ .0001).

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Total nitrogen (TN) and crude protein (CP) in the northern orientation were 27% higher (p = 0.022 and 0.024) than corresponding values in the southern orientation. These parameters also increased significantly (p = 0.05) with distance from the tree row in both orientations with values at 4 m being the highest (in the north-facing plots) and/or similar to those at 6 m (in the south-facing plots). However, dry matter content (DM), acid detergent fibers (ADF) and neutral detergent fibers (NDF) were not affected by the distance from the tree row, orientation of oats plots and their interactions (data not shown).

Discussion and Conclusions

Generally competitive interactions occur in a zone close to the tree row and depending on the species type, age, and height of a tree; and soil and climatic conditions, this zone may be within at 2-m from the tree row (Thevathasan and Gordon, 2004). Lower SMC and PAR at 2 m from the

15 16 17 18 19 20 21 0-20 20-40 40-60 S o il M o is tu re C o n te n t (% )

Soil Sampling Depth (cm) a b c 0 400 800 1200 1600 2000

Morning Solar noon Evening

PA R ( μ m o l m − 2 s −1) Time of day North South c c b a d d

Figure 1: Gravimetric soil moisture content at three sampling depths in the Manitoba Alley cropping system at Indian Head, SK. Means (± SE) followed by same letters are not significantly different at P ≤ 0.05 according to Tukey's HSD

Figure 2: Photosynthetically active radiation in the Manitoba Alley cropping system at Indian Head, SK. Means (± SE) followed by same letters are not significantly different at P ≤ 0.05 according to Tukey's HSD

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from the tree row did not translate into increased DM of oats. This would suggest that other factors, apart from soil nutrients, were driving yield and growth of oats. Thus, comparatively higher SMC and DM in the northern orientation than in the southern orientation imply that yield and nutrition of oats in this semiarid area of the prairies was driven by SMC. Beyond the 2-m zone, there were little effects of trees on tested biophysical parameters and on oats yield and nutrition. This is partly attributed to the age and architecture of the Manitoba maple. When this study was conducted, the tree was 9 years old, 3 m high and had no spreading canopy such that it could compete vigorously with oats for above-and below-ground resources. Moreover, as a C3 plant, oats is not sensitive to shade and has a higher light saturation point (> 1.200 μmol m−2 s−1; Nair, 1993) than the range noted in this study (400-1.000 μmol m−2 s−1). Thus it can be concluded that producers may integrate Manitoba maple trees on farms to diversify production cycles without comprising forage crop yields and nutrition because no significant adverse effects were noted within 6 m from the tree row during the first decade of tree establishment. However, it is important to monitor tree-crop interactions noted here to note any changes with age and recommend appropriate management for optimizing system productivity.

References

Thevathasan and Gordon. 2004. Agroforest. Syst. 61: 257 - 268 Cardinael et al. 2012. Agrofor. Syst. 86:279-286

Nair, P.K.R., 1993. An Introduction to Agroforestry. Kluwer Academic Publishers, Dordrecht, The Netherlands Kort, J. and R. Turnock. 1999. Agroforest. Syst. 44: 175 - 186.

Marchand, P.P. and S. Masse, 2008. Natural Resource Canada, Canadian Forest Service. 96 p. Also available in PDF format at http://bookstore.cfs.nrcan.gc.ca

Doughterty, M.C., N.V. Thevathasan, A.M. Gordon, H. Lee and J. Kort. 2009. AGEE. 131: 77- 84

Jose, S., A.R. Gillespie and S.G. Pallardy. 2004. Interspecific interactions in temperate agroforestry. Agroforest. Syst. 61: 237-255

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Soil carbon sequestration in a Mediterranean agroforestry system

Cardinael R1,3*, Chevallier T1, Barthès B1, Dupraz C2, Chenu C3 *Corresponding author: remi.cardinael@supagro.inra.fr

1

IRD, UMR Eco&Sols, Montpellier SupAgro, Bâtiment 12, 2 place Viala, 34060 Montpellier, France

2

INRA, UMR System, Montpellier SupAgro, Bâtiment 27, 2 place Viala ,34060 Montpellier, France

3 _{AgroParisTech,}_{UMR Bioemco, Bâtiment Eger, Avenue Lucien Brétignières, 78850 Thiverval-Grignon, France}

Introduction

The Earth soils are a large reservoir of carbon (C), containing about 1.500 PgC, which represents two to three times the C contained in the atmosphere. This reservoir is extremely sensitive to land use and can act as a source or as a sink of atmospheric carbon dioxide (CO2).

Agroforestry systems are expected to sequester C into both above and belowground biomass. Such systems could also increase soil organic carbon (SOC) stocks due to higher organic inputs including leaf litter, pruning residues, tree fine root turnover, and root exudates. However, although agroforestry systems have been thoroughly investigated in tropical regions, their potential for C sequestration has rarely been studied in temperate regions, and when studied, has mostly concerned superficial soil layers (Lorenz and Lal 2014). The objectives of this study were (i) to quantify the SOC stocks down to 2 m soil depth in an 18-year-old agroforestry system and in an adjacent agricultural plot, (ii) to study spatial distribution of SOC stocks, especially in relation to the distance from the trees, and (iii) to assess which SOC fractions are responsible for possible differences between treatments.

Material

The experimental field was established in 1995 in Prades-le-Lez (longitude 04°01’ E, latitude 43°43’ N, elevation 54 m a.s.l.), near Montpellier, South of France, on an alluvial carbonated Fluvisol. The climate is sub-humid Mediterranean with an average temperature of 14.5°

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May 2013, about 200 soil cores were sampled down to 2 m depth into these two plots. Each soil core was cut into ten layers, and bulk densities were measured for each of them, as well as texture and SOC contents, which were either analyzed conventionally (dry combustion after decarbonatation) or predicted using field visible and near infrared spectroscopy (Gras et al. 2013). Carbon stocks were spatialized at the field scale. To determine which SOC fractions were affected by the agroforestry system, soil particle-size fractionation (Gavinelli et al. 1995) was performed on 64 soil samples, collected at 0-10, 10-30, 70-100 and 160-180 cm soil depth.

Results

Soil carbon stocks were characterized by a high, but organized spatial variability. Spatial analysis showed twice higher SOC topsoil content on the tree rows compared to the inter-rows. Whereas the SOC stock in the reference agriculture plot was 42.29 ± 0.53 MgC ha-1 (0-30 cm) and 118.48 ± 0.88 MgC ha-1 (0-100 cm), in the inter-row significant additional storage of 2.5 ± 0.80 and 3.5 ± 1.29 MgC ha-1 was observed at 0-30 and 0-100 cm, respectively. On the tree row, additional storage was 17.5 ± 1.06 and 20.5 ± 1.50 MgC ha-1respectively,compared to the agricultural plot. Below 1 m depth, SOC stocks did not differ. Knowing that tree rows represent 16% of the agroforestry plot, we calculated the additional SOC storage of the whole field compared to the control plot. Annual additional SOC storage rates were estimated at 272 ± 68 kgC ha-1 yr-1 (0-30 cm) and 352 ± 98 kgC ha-1 yr-1 (0-100 cm). This additional storage was mainly due to the particulate organic matter fraction (50-200 and > 200 µm), whereas only 10 to 15% was associated to clay particles (< 2 µm). Total organic carbon storage rate would reach about 1.2 MgC ha-1 yr-1 when trees biomass was also taken into account.

Discussion

High SOC contents on the tree rows were mainly due to high inputs from the natural vegetation. No clear pattern of SOC content was observed in relation to the distance to the trees, but the tree row had an important impact on the SOC storage of the agroforestry field due to the spontaneous vegetation. This is an indirect effect of agroforestry systems: the tree row also acts as a permanent pasture, and has a positive impact on SOC sequestration. Additional SOC storage rates are higher than those commonly reported for other techniques used to improve SOC in agriculture, such as no-till farming or conservation agriculture (Pellerin et al. 2013). Up to now, additional storage is mainly limited to topsoil layers and in labile organic fractions, making it an unstable storage.

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References

Gavinelli E, Feller C, Larré-Larrouy M., et al. (1995) A routine method to study soil organic matter by particle-size fractionation: examples for tropical soils. Commun Soil Sci Plant Anal 26:1749–1760.

Gras J-P, Barthès BG, Mahaut B, Trupin S (2013) Best practices for obtaining and processing field visible and near infrared (VNIR) spectra of topsoils. Geoderma 214-215:126–134.

Lorenz K, Lal R (2014) Soil organic carbon sequestration in agroforestry systems. A review. Agron Sustain Dev 34:443–454.

Mulia R, Dupraz C (2006) Unusual fine root distributions of two deciduous tree species in southern France: What consequences for modelling of tree root dynamics. Plant Soil 281:71–85.

Pellerin S., Bamière L., Angers D., Béline F., Benoît M., Butault J.P., Chenu C., Colnenne-David C., De Cara S., Delame N., Doreau M., Dupraz P., Faverdin P., Garcia-Launay F., Hassouna M., Hénault C., Jeuffroy M.H., Klumpp K., Metay A., Moran D., Recous S., Samson E., Savini I., Pardon L., 2013. Quelle contribution de l’agriculture française à la réduction des émissions de gaz à effet de serre ? Potentiel d'atténuation et coût de dix actions techniques. Synthèse du rapport d'étude, INRA (France), 92 p.

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Pasture management under hardwood plantations: legume

implantation vs. mineral fertilization

López-Díaz M L, Moreno G*, Bertomeu M *Corresponding author: gmoreno@unex.es Forestry Research Group, University of Extremadura, Spain

Introduction

Europe has a shortage of quality wood and therefore there is a growing interest in the establishment of hardwood plantations. In Spain, hardwood species are commonly harvested after long rotations of up to 50 or 60 years. But with intensive management, including irrigation, fertilization and chemical weed control, rotation length can be notably reduced by half (to 20-25 years). Fertilization and herbicide application are the most controversial management practices because of the high costs involved and their impact on soil and water pollution. The implantation of forage legumes could reduce the economic costs of these plantations, improve pasture production and quality, and optimize the environmental functions of these plantations, i.e. provide soil cover to control erosion (Gselman and Kramberger, 2008; McCarteney and Fraser, 2010). However, the competition for soil water and nutrients by forage legumes can reduce tree growth. The objective of this project is to study the response of trees and pasture in a silvopastoral system established in an intensively managed hardwood plantation, to the implantation of legumes as nitrogen fertilizer, and its environmental implications.

Materials

The experiment was carried out in Extremadura (Spain) in a 15- year old hybrid walnut (Juglans major x nigra mj 209xra) plantation, with a density of 333 trees ha-1. Three treatments were applied during three years (2011 -2013): mineral fertilization, that consisted in the application of 40 kg N ha-1, 40 kg P2O5 ha-1 and 50 kg K2O ha-1; sowing of legumes (complemented by the

same quantities of PK as mineral treatment); and control treatment, combined with three levels of irrigation. In October 2011 and 2013, a mixture of 25 kg ha-1 of Trifolium michelanium and 10 kg ha

-1

of Ornithopus compresus were sown under trees. Three replicates were used for each combination of fertilization (3) and irrigation (3) treatments that results in nine combinations and 27 plots. Each plot (95 x 15m) comprised two rows of 20 trees. Pasture production, tree normal diameter growth, soil carbon, available soil nutrients (N, P, K and Ca) and nitrate leaching were studied. For determining pasture production, three herbage samples (50x50 cm) were taken from

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each plot using hand clippers at a height of 2.5 cm in June 2013. After that, herbage samples were dried in an oven at 80ºC for 48 h. In May 2013, 12 ion exchange resins were installed at 15 cm depth in each plot (six for cations and six for anions). In June 2013 (one month later), they were taken out and analyzed in a laboratory. For determining nitrate leaching, two ceramic cup samplers were installed in each plot at 30, 60 and 90 cm and samples were taken periodically from the beginning of 2013. Tree diameter at breast height (dbh) was measured. Data were analysed as randomized design by ANOVA and LSD test to separate treatment means when ANOVA showed significant effects (p<0.05). All statistical analyses were performed using R program.

Results

The results obtained (Table 1) indicate that legumes significantly increased the N available (21.6±3.1 μg N / 50 cm2

/ month). With respect to the other nutrients, levels of nutrient availability (2.3±0.5 μg P / 50 cm2

/ month, 65.3±7.7 μg K / 50 cm2 / month and 39,1±1.1 μg Ca / 50 cm2 / month) were similar to those obtained with mineral fertilization (3.6±0.8 μg P / 50 cm2 / month, 62.1±8.1 μg K / 50 cm2 / month and 38.1±0.9 μg ca / 50 cm2 / month) and higher than in the control. However, nitrate leaching was slightly higher under legume sowing (20.6±3.6 mg NO3- l),

but there were no differences below this depth (data not included).

The application of mineral fertilizer produced the highest increment of tree diameter (4.2±0.1 cm) followed by legume sowing (3.7±0.1) and control (3.3±0.1 cm). In the case of pasture production, mineral fertilization (5.9±0.3 t ha-1) and legumes (6.4±0.3 t ha-1) showed similar values and higher than control (3.5±0.3 t ha-1). In any case, there were significant responses to irrigation treatments.

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Treatments Elements Control Mineral Legumes sign Soil N 7.4±0.8b 9.6±2.2b 21.6±3.1a *** P 1.7±0.3b 3.6±0.8a 2.3±0.5ab * K 29.5±2.1b 62.1±8.1a 65.3±7.7a *** Ca 37.0±0.8 38.1±0.9 39.1±1.1 ns Grounwater pollution NO3- 13.9±1.7 14.5±2.1 20.6±3.6 ns(0.16)

Tree growth Diameter increment

3.3±0.1c 4.2±0.1a 3.7±0.1b ***

Pasture production

3.5±0.3b 5.9±0.3a 6.4±0.3a ***

Table 1. Nutrient (N, P, K, Ca; μg / 50 cm2 / month) availability in soil, nitrate leaching (mg N-NO3

l-1), diameter increment (cm) in trees and pasture production (t ha-1) with different fertilization treatment.

Discussion and conclusions

The use of legumes increased the available nutrients in soil, especially nitrogen, whose value increased by almost 200% compared to control. Gabriel and Quemada (2010) have also observed positive responses in soil nitrogen to the application of legumes as green manure. However, a portion of the nitrogen fixed by legumes could be leached and result in water contamination. In fact, nitrate leaching increased under legumes, although only in the uppermost soil layer (0-30 cm). However there is no difference among treatment below this depth. This could be explained because the contribution of N fixed by legumes occurs gradually (Marinari et al., 2010). Moreover, López-Díaz et al. (2010) have observed that the pasture and tree combination was effective in reducing nitrate pollution in water as a result of the presence of tree roots at greater depths that can use this nitrogen (Moreno et al., 2005), and avoid water contamination (Defauw et al., 2005).

The highest pasture production was obtained with legumes, which additionally increased the quality of forage (Rigueiro-Rodríguez et al., 2007). This can explain the reduction of tree growth that was observed compared with the mineral application treatment. Moreover, the nitrogen supplied by the legume occurs gradually (Marinari et al., 2010), Therefore it is possible that better results can be obtained in the long term.

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In conclusion, the sowing of legumes as an alternative to N mineral fertilizers can improve the profitability of silvopastoral systems developed in quality timber tree plantations.

References

Defauw SL, Sauer TJ, Kristofor RB, Savin MC, Hays PD and Brahana J (2005) Nitrate-n distributions and denitrification potential estimates for an agroforestry site in the ozark highlands, USA. AFTA 2005 Conference Proceedings. 13 pp

Gabriel J and Quemada M (2010) Replacing bare fallow with cover crops in a maize cropping system: Yield, N uptake and fertiliser fate. at http://www.scopus.com/inward/record.url? Gselman A and Kramberger B (2008) Benefits of winter legume cover crops require early sowing.

Australian Journal of Agricultural Research 59: 1156-1163

López-Díaz ML, Rolo V and Moreno G (2011) Tree's Role in Nitrogen leaching after organic, mineral fertilization : a greenhouse experiment. Journal of Environmental Quality 40: 1-7 Marinarii S, Lagomarsino A, Moscatelli M, Di Tizio A and Campiglia E (2010) Soil carbon and

nitrogen mineralization kinetics in organic and conventional three-year cropping systems. Soil and Tillage Research 109: 161-168

McCartney D and Fraser J (2010) The potential role of annual forage legumes in Canada: A review. Canadian Journal of Plant Science 90: 403-420

Moreno G, Obrador JJ, Cubera E and Dupraz C (2005) Fine root distribution in Dehesas of Central-Western Spain. Plant and Soil: 277: 153–162

Rigueiro-Rodríguez A, Mosquera-Losada MR and López-Díaz ML (2007) Mineral concentrations in herbage and soil in a pinus radiata silvopastoral system in north-west Spain after sewage sludge and lime application. Grass and Forage 62: 208-224.

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Carbon Sequestration in a Poplar Agroforestry System in India with

Wheat and other Crops at Different Spacing and Row Directions

Dhillon R S1, Beniwal R S1, von Wuehlisch G*2

*_{Corresponding author: georg.vonwuehlisch@ti.bund.de} 1

Department of Forestry CCS Haryana Agricultural University, Hisar-125004, India

2

Thünen-Institute for Forest Genetics, Sieker Landstr. 2, 22927 Grosshansdorf, Germany

Introduction

Owing to its fast growth, deciduous nature, marketing acceptability, and successful intercropping, poplar has become a viable alternative to traditional irrigated rice-wheat rotation in north-western states of India and satisfies the rising requirements of the regional plywood industry. Agroforestry provides multiple ecological and economic benefits including carbon sequestration, soil and water improvement, raising species diversity and stabilizing farmer’s incomes by diversification. Experiments were conducted to study the effect of poplar spacing and row direction, suitable crop rotation as well as the carbon sequestration potential of agroforestry as compared to sole agriculture. Furthermore, changes in soil physico-chemical properties were analyzed.

Material and Methods

In Experiment No. 1, the treatments were (A.) Poplar planting spaces: a) 5 x 4 m b) 10 x 2 m c) 18 x 2 x 2 m (paired row) an (B.) crop rotations a) cowpea (Vigna unguiculata)-wheat (Triticum

aestivum) b) sorghum (Sorghum bicolor)-berseem (Trifolium alexandrinum) c) fallow. The design

was split plot in three replications. In Experiment No. 2 poplars were planted along bunds in (a.) North-South, (b.) East-West direction. In the study, the wheat crop was sown during the first week of November and harvested in April. The carbon storage potential of agricultural crops was equated 50 % of the total above ground dry biomass produced by these crops during the six years. The carbon storage potential of poplar at six years age was estimated by felling the trees and recording their dry biomass as well as the leaf and branch fall over the six years.

Results

The height of poplar was not affected significantly at different planting spaces as well as under agroforestry and sole poplar land uses. However, the girth of poplar under agroforestry was significantly more than sole poplar. Paired row planting (18 x 2 x 2 m) of poplar resulted in

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significantly less girth than planting of poplar at 5 x 4 m and 10 x 2 m spacing due to increased competition among plants for different growth resources. Leaf fall of poplar decreased with decreasing plant spacing on account of reduced crown size. Except for nitrogen and potassium only little amounts of P were added to the soil through leaf litter fall at all planting spaces of poplar. However leaf litter fall during the six years have helped in maintaining the organic carbon content of soil. The yield of the grain and straw decreased sharply from 15 to 65 % under one to six year duration. Organic carbon content in the top soil increased considerably under agroforestry crops with 0.36 % under the six year plantation and 0.22 % under the control. The carbon stock in different carbon pools under study indicated that the above-ground biomass followed by below-ground biomass accumulated to 39 t/ha at the age of six years under the agroforestry system compared to 4.9 t/ha of the control.

The performance of agricultural crops during the kharif season (summer-autumn) were affected by uneven distribution of rainfall as a result of which crops had to face moisture stress especially under poplar. The green fodder yield of sorghum increased with increasing row spacing and was in the control field was significantly higher than all the spacings of poplar. Cowpea for fodder was found more compatible with poplar than sorghum. The green fodder yield of cowpea at 18 x 2 x 2 m spacing of poplar was significantly higher than 5 x 4 m and 10 x 2 m spacings which were at par with each other.

During the rabi season (winter-spring), the yield of both berseem and wheat increased with increasing row spacing, however, the differences between 5 x 4 m and 10 x 2 m spacings were not significant. The mean decrease in the yield of berseem and wheat under poplar was 20 and 39 % respectively, over control. The poplar contributed the maximum carbon in the poplar-wheat system. The carbon stock in the above-ground biomass followed by below-ground biomass contributed the maximum (37.3 t/ha at the age of six years) towards aggregate carbon pool under agroforestry system. The timber carbon content was estimated to be 28.31 t ha-1, whereas, the contribution of

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intercropping systems compared to those from the sole cropping system were due to the additional carbon pool in the trees and an increased soil carbon pool as a result of carbon from litter fall and root turnover. However, these figures depend upon the assumption that the harvested biomass (timber) goes to durable products, and litter/branches/ roots are not removed from the system but completely added in the soil. Still, the contribution of tree stem and roots play an important role in carbon sequestration in the agroforestry system.

Poplar based sorghum-berseem crop rotation had higher carbon storage potential than the sole crop. The sequestration was 77, 69 and 59 % higher at 5 x 4 m, 10 x 2 m and 18 x 2 x 2 m spacing of poplar than in sole agriculture, respectively. Due to less crop biomass production in cowpea- wheat crop rotation in sole crops, carbon storage under agroforestry was 111, 98 and 88 % higher at 5 x 4 m, 10 x 2 m and 18 x 2 x 2 m spacing than the sole crops, respectively. The mean rate of carbon storage in agroforestry has been found to be 82 % higher than sole agriculture. Moreover, the carbon stored in tree component is locked for a long time whereas the carbon in crops is locked for a short period only.

Effect of row direction on the performance of crops with poplar showed that poplar planted on East-West field bund affected the green fodder yield of sorghum up to 9-12 m and wheat up to 3-6 m distance from the tree line. The green fodder yield of sorghum and grain yield of wheat increased significantly with increasing distance from the tree line up to 12 m and 6 m distance respectively, and after that no significant variation in yield was recorded. The yield of sorghum was found to be significantly higher on southern aspect than the northern aspect due to availability of more sunlight on southern aspect of tree line. However aspect had no significant effect on grain yield of wheat at 12 and 6 m distance, respectively. The poplar planted on North - South field bund also affected the green fodder yield of sorghum up to 9-12 m and wheat 3-6 m distance from the tree line. The green fodder yield of sorghum and grain yield of wheat increased significantly with increasing distance from the tree line up to 12 m and 6 m respectively.

Discussion

Rabi crops like cereals are suited to partner deciduous trees. The crop grows strongly during the initial period from November to mid March, when shading is not a problem. By the time the poplars have developed foliage, the cereal crop is completing its vegetative growth and the ripening of the crop is delayed by two weeks. Kharif crops are affected by shading and competition for water of the fully leaved poplars. Distance to the trees and row direction are therefore of strong

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influence on crop productivity. The study strongly reinforces poplar-crops association a better option than the sole agricultural cropping, not for carbon mitigation only but for sustainable productivity as well as profitability.

Main Results

1. After six years of plantation, poplar has been found to attain significantly more girth at 5 x 4 m and 10 x 2 m spacing’s than paired row planting (18 x 2 x 2 m).

2. Sorghum and cowpea grown for fodder during the kharif season and wheat and berssem (fodder) grown during the winter season produced significantly higher yield in paired row planting than 5x4 m and 10x2 m spacing’s.

3. Poplar based agroforestry system at six years age was found to sequester 82 % more carbon than sole agriculture. The rate of carbon storage was found to be 17.8 t/ha/year in poplar based agroforestry system and 9.8 t/ha/year in sole agriculture.

4. Six years old poplar planted on field bunds has been found to affect the green fodder yield of sorghum up to 12 m distance and wheat grain yield up to 6 m distance from the tree line.

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A methodological framework for quantification and valuation of

ecosystem services of tree-based intercropping systems

Alam M1, Olivier A1*, Paquette A2, Dupras J3, Revéret J-P4, Messier C5 * Corresponding author: Alain.Olivier@fsaa.ulaval.ca

1

Département de phytologie, Université Laval, Québec, Canada

2

Center for Forest Research, Université du Québec à Montréal, Montréal, Canada

3

Département de géographie, Université de Montréal, Montréal, Canada

4_{Département stratégie, responsabilité sociale et environnementale, Université du Québec à Montréal, Canada} 5_{Institut des sciences de la forêt tempérée (ISFORT), Université du Québec en Outaouais, Ripon, Canada}

Introduction

Agricultural intensification has raised environmental concerns such as soil erosion, water pollution, and degradation of biological diversity in rural landscapes. In view of these ecological problems related to conventional agriculture, a pressing question is how to simultaneously increase agricultural production while conserving a healthy and well-functioning life support system. Recently, agroforestry has been seen as an option to work at the interface of these global challenges. Studies have shown that this land use system has the potential to maintain productivity and improve ecological functions in agricultural landscapes, while helping to mitigate climate change impacts. Despite the demonstrated contribution of agroforestry systems in producing ecological services (ES), economic analyses on non-market services, as well as on the potential trade-offs between bundles of services, are sparse. Some studies provide a general account of the role of agroforestry systems in providing ES, while others provide frameworks for cost-benefit analysis of agroforestry systems in the tropics. However, a comprehensive analytical framework for quantifying and valuing ES is missing in the context of temperate systems. In view of this research gap, a framework has been developed for the valuation of ES of a tree-based intercropping (TBI) system in southern Québec, Canada, as a case study. The framework also answers several practical questions such as the profitability of TBI systems as a long-term investment when

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non-services for analysis. In the second step, we quantified the service providing units and their relationships with the provision of services. In the third step, we attempted economic valuation of each of the ES. The final step involved extrapolation of results and examination of trade-offs. The evaluated ecosystem services were: nutrient mineralization, water quality, soil quality, pollination, biological control, air quality, windbreak, timber provisioning, agriculture provisioning and climate regulation.

Results

This study provides the first estimate of economic values of ES generated by TBI systems. The values ranged from 24 CAN$ ha-1 y-1 for pollination to 785 CAN$ ha-1 y-1 for agricultural products. Water quality regulation ranked highest among the non-market services, followed by air quality regulation and carbon sequestration. Although conventional agriculture provides more private benefits than TBI, the value of ES of TBI to society is much higher compared to this private value.

The total annual margin of TBI ecosystem services was estimated to be 2.645 CAN$ ha-1 y-1. The economic value of combined non-market services was 1.634 CAN$ ha-1 y-1, which was higher than the value of marketable products (i.e. timber and agricultural products) combined. The economic return from agriculture in monoculture was 1.110 CAN$ ha-1 y-1, whereas the return from agriculture in TBI was 785 CAN$ ha-1 y-1.

We also performed an analysis of the present value of future benefits of ES for a rotation of 40 years. Provision of agricultural products ranked highest (16.287 CAN$ ha-1) among the ES, followed by water quality (11.581 CAN$ ha-1), air quality (9.510 CAN$ ha-1), carbon sequestration (7.346 CAN$ ha-1), and soil quality (3.631 CAN$ ha-1). Total economic value of all the services was 54.782 CAN$ ha-1, only a third of which was contributed by agricultural products. Total non-market benefits were twice as high as the provisioning services combined (i.e. timber and agriculture).

Discussion (and conclusions)

The total potential value of TBI ecosystem services estimated in this study was 5 billion dollars a year in the province of Québec. Many farmers in Canada are adopting agroforestry for farm and societal benefits. The 2006 census data reveals that in Québec alone 5.994 farms out of 30.675 reported to have windbreaks, compared to 1.845 in 2001. Such a trend in the adoption of trees in agricultural landscapes suggests that farmers could positively respond to TBI systems if they found them to be profitable. However, since the private benefits from TBI systems are less than the

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societal benefits in terms of provision of ES, government programs to subsidize farmers would be necessary to entice them to adopt TBI systems rapidly. The question, however, is determining what such programs could be? Payment for ecosystem services is regarded as an effective mechanism for managing sustainable provision of these services from landscapes and watersheds. Although most successful payment programs have been implemented in developing countries, there is evidence that such mechanisms can equally work in industrialized nations.

In the current context of agro-environment programs applicable in Québec, agroforestry practices are recognized and supported as are other agricultural beneficial management practices, essentially for specific ecological functions such as stabilizing riverbanks, reducing erosion and improving habitats for biodiversity. However, agroforestry systems differ from the majority of agricultural beneficial management practices in their ability to generate income through the production of various products and services possessing tangible economic value. For this reason, adopting programs focusing on both the private profitability of agroforestry practices and their public benefits is a fundamental issue.

To summarize, despite inherent uncertainties in quantification and valuation of ecosystem services, which are non-market in nature, this study provides a reasonable estimate of the economic contribution of tree-based intercropping systems to society’s welfare. The demonstrated benefits are substantial. However, in the Québec context, the management of TBI systems still needs to be optimized in order to make it more profitable for farmers than is conventional agriculture, as already observed in Europe. The benefits of their ecosystem services are realized at the cost of farmers’ private benefits due to reduced provisioning services and the expected cost of adoption and maintenance of this new technology over a longer time frame. While it is impractical to suggest that all agricultural lands should be converted to agroforestry, a land inventory can determine the areas suitable for TBI based on environmental and technical feasibility and the willingness of the farmers in participating. Therefore, the adoption and expansion of TBI systems in

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The role of Rural Development Policy in supporting agroforestry

systems in EU

Pisanelli A1*, Marandola D2, Marongiu S2, Paris P1, Rosati A3, Romano R2 *Corresponding author: andrea.pisanelli@ibaf.cnr.it

1

Istituto di Biologia Agro-ambientale e Forestale, Consiglio Nazionale delle Ricerche, Italy

2

Istituto Nazionale di Economia Agraria, Italy

3

Consiglio per la Ricerca e la Sperimentazione in Agricoltura, centro di ricerca per l'olivicoltura e l'industria olearia, Italy

Introduction

Agroforestry systems comprise land use practices in which woody perennials are deliberately grown on the same land management unit with crops and/or animals (Nair, 1993). These systems are traditional practices that formed key elements of European rural landscapes until modern agriculture was introduced, since trees served various purposes in the agrarian economy such as the production of fruits, fodder, wood or timber as well as environmental benefits (Eichhorn, 2006). The introduction of modern management techniques in agriculture such as new crop varieties, fertilisers, and large-scale machinery caused the transformation of traditional agroforestry practices, reducing tree components in rural landscape and producing undesirable social and environmental consequences. Recent research findings have demonstrated that agroforestry systems can play an important role in improving productivity and profitability for farmers (Graves et al., 2007) and providing environmental benefits (Palma et al., 2006). The Common Agricultural Policy (CAP) recognises that the establishment of agroforestry systems should be encouraged due to their “high ecological and social value” (EU Regulation 1698/2005). A financial support was thus introduced in the EU Rural Development Programmes (RDPs) during the 2007-2013 programming period, aiming at promoting the first establishment of new agroforestry systems on arable lands (measure 222). This financial support should be proposed again in the future RDPs, 2014-2020 (Marandola, 2013). The objectives of this paper are to: i) assess the implementation rate of the measure 222 in EU27 during the 2007-2013 programming period; ii) identify the main reasons that influenced the farmers’ interest in the measure 222; iii) highlight the perspectives and opportunities for agroforestry systems in the next RDPs 2014-2020 programming period.

Material

The data on RDPs monitoring were collected and analysed consulting the European Network for Rural Development (http://enrd.ec.europa.eu). The study was carried out comparing the financial resources allocated to implement the measure 222 with: i) the resources allocated to

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implement other forestry measures; ii) the effective expenditures invested in establishing new agroforestry systems. The output indicators (number of beneficiaries and hectares under new agroforestry systems) were also analysed in relation to their expected target. Future perspectives of agroforestry systems in the next RDPs (2014-2020) were assessed through an open consultation conducted by the recently constituted European Agroforestry Federation, EURAF (http://www.agroforestry.eu) and carrying out a survey addressed to RDPs Managing Authorities.

Results

The forestry measures of the RDPs are aimed at improving the economic, social and environmental dimensions of forests to promote their sustainable management and their multifunctional role (European Commission, 2009). At EU 27 level, during the 2007-2013 programming period, a total amount of about 7.5 billion of Euro have been allocated to implement the forestry measures, of which almost 4 billion have been effectively spent at the end of 2013, with an average implementation rate of 52.4 %.

Among the forestry measures, almost 90 % of the total resources have been allocated to the measures 221 (First afforestation of agricultural land), 226 (Restoring forestry potential and introducing prevention actions) and 227 (Non-productive investments). Few EU regions and countries (table 1) have allocated resources to implement the measure 222, for a total amount of about 15 million of Euro (0.2 % of the resources allocated to all the forestry measures). More than half of the resources available to implement measures 221 and 226 have been invested. Instead, only 3.4 % of the resources allocated to the measure 222 have been effectively spent. In terms of output indicators, measure 222 reached only 2.3 % of the expected beneficiaries (farmers and land owners) and only 2.1 % of the expected hectares has been realised (table 2).

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excluding, for example, agro-silvopastoral systems that are common in Mediterranean area); iii) the lack of funding to cover management costs of the systems; iv) the conflict between the measure 222 and other CAP instruments such as the Single Farm Payment, according to which the presence of trees reduces the amount of direct farm payments (Pisanelli et al., 2012). The EURAF conducted a lobby activity at European Parliament and through a position paper has remarked the importance to improve the next RDPs, for the period 2014-2020, to allow European farmers to adopt agroforestry systems.

It is thus expected that the above mentioned limits will be removed in the next RDPs. Article 23 of the EU Reg. 1305/2013 on support for rural development by the European Agricultural Fund for Rural Development (EAFRD) 2014-2020 asserts that: i) agroforestry systems comprise the combination between forestry plantations and agriculture on the same land; ii) grants should cover both the establishment costs (up to 80 % of the expenses) and the management costs with an annual premium for 5 years; iii) beneficiaries should be not limited to farmers but may include also Municipalities and Associations.

Table 1: resources allocated to the measure 222 and realised expenditures at country level during the RDPs 2007-2013 programming period.

Country Regions Allocated

resources Financial execution Implementation rate in 000€ in 000€ In % Belgium Flanders 500 0 0

France Guadeloupe, Guyane 3.228 39 1.2

Hungary 2.813 380 13.5

Italy Marche, Lazio, Umbria, Veneto, Sicilia 1.300 10 0.8

Portugal Mainland, Azores 6.804 93 1.4

Spain Aragón, Asturias, Canarias, Extremadura, Galicia 411 0 0

Total EU27 15.056 522 3.4

The delegated acts, which are being finalized between the Commission, the Council and the Parliament, will decide the practical details in the implementation of the EU Reg. 1305/2013. However, it seems that the new grant scheme should be more attractive for farmers and, consequently, it is expected that the adoption of agroforestry systems should increase at EU level. This would beneficial to target crucial rural development priorities such as: i) restoring, preserving

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and enhancing ecosystem services, ii) promoting efficiency resource use, iii) supporting the shift towards a low carbon and climate resilient economy in agricultural and forestry sectors.

Table 2: output indicators assessing the implementation rate of the measure 222 during the RDPs 2007-2013 programming period.

Beneficiaries (n) Area (ha)

Country Target Realised Implementation

rate Target Realised

Implementation rate Belgium 75 0 0 250 0 0 France 610 4 0.7 3.032 34 1.1 Hungary 300 59 19.7 3.000 594 19.8 Italy 1.032 1 0.1 6.729 9 0.1 Portugal 575 0 0 15.025 0 0 Spain 205 0 0 1.600 0 0 Total EU27 2.797 64 2.3 29.636 637 2.1 References

Eichhorn MP, Paris, P,Herzog F, Incoll LD, Liagre F.,Mantzanas K, Mayus M, Moreno G,

Papanastasis VP,Pilbeam DJ, Pisanelli A, Dupraz C (2006) Silvoarable Systems in Europe: past, present and future prospects. Agroforestry Systems, 67: 29-50.

European Commission (2009) Report on the implementation of forestry measures under the rural Development Regulations 1698/2005 for the period 2007-2013.

http://ec.europa.eu/agriculture/fore/publi/report_exsum_en.pdf.

Graves AR, Burgess PJ, Palma JHN, Herzog F, Moreno G, Bertome M, Dupraz C, Liagre F, Keesman K, van der Werf W, van den Briel JP (2007) Development and application of bio-economic modelling to compare silvoarable, arable and forestry systems in three European countries. Ecological Engineering 29: 434–449.

Marandola D (2013) La riforma UE post 2013 per lo sviluppo rurale. In (a cura di) Cesaro L, Romano R, Zumpano C Foreste e politiche di sviluppo rurale: stato dell’arte, opportunità mancate e prospettive strategiche. Collana Studi e Ricerche INEA, Osservatorio Politiche Strutturali.

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Towards a joint strategy for Iberian oak agroforestry systems:

acknowledging the value of dehesas and montados

Fernando P1*, Pinto-Correia T2, Ribeiro N2, Potes J3, Moreno G1, Beaufoy G4 * Corresponding author: nando@unex.es

1

Forest Research Group, University of Extremadura, Spain

2

ICAAM, University of Evora, Portugal

3

Escola Superior Agrária de Santarém

4_{European Forum on Nature Conservation and Pastoralism}

The Iberian working oak woodlands (dehesas in Spain and montados in Portugal) are biodiversity-rich, savanna-like extensive grazing systems. They are considered as outstanding High Nature Value (HNV) farming systems and the most extensive agroforestry system in Europe according to CORINE Land Cover. Dehesas extend over 3.5 million hectares in Spain, mainly covered by holm oak (Quercus ilex) and devoted to livestock raising, while montados occupy 1 million hectares where cork extracted from cork oak (Q. suber) is the main product. Both dehesas and montados are, however, examples of multipurpose systems in which a variety of land uses coexists in a landscape mosaic within farms ranging in size from 100 to 10000 hectares.

Large-scale analysis of Iberian oak agroforestry territories has shown a trend towards intensification in the more productive sites and abandonment in marginal lands. Intensification results in tree regeneration failure and soil erosion, whereas marginalization enhances shrub encroachment. Although reduced landscape heterogeneity in both cases seems to result in lower species richness, shrub encroachment, which is a common trend in protected areas or big game states, is important for a number of endangered species. As an additional threat, oak decline due to root pathogens and water stress is severely reducing tree cover on many farms.

Economic analyses of dehesas and montados show moderate to low profitability of most farms, with a high dependence on public subsidies from the CAP at least in the Spanish case. To date, intensive management practices have been used to increase short-term profitability. Thus, stocking rates have dramatically increased in dehesas at the expense of tree regeneration. Similarly, cork production in most montados requires intensive shrub control, a practice that reduces regeneration and provokes soil erosion. Therefore, profitability is often achieved at the expense of environmental sustainability.

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In the last few years increased awareness of the profitability-sustainability dilemma, has led stakeholders and researchers from both countries to develop joint initiatives. Firstly, a comprehensive technical report has been produced in each country. In addition, an Iberian condensed report has been delivered to establish the main challenges shared by both agroforestry systems: (1) to increase the social and political awareness of the economic and environmental importance of dehesas and montados; (2) to create two coordinated national institutes integrating research and development efforts; (3) to ask for national and EU policies focussed on the whole agroforestry system rather than on particular components; and (4) to improve marketing strategies and certification of environmentally friendly products.

Policy measures should consider these priorities in an integrated way. The main decisions are now made at national level, in the Portuguese case, and at the regional level, in the Spanish. There should therefore be room for specific schemes considering the specific land use systems in each country/region. The EU Rural Development Programme regulations give priority to HNV farming systems, especially within the so-called agri-environmental measures, but these measures need to be implemented on a much larger scale in dehesa and montado territories and they will only work if supported by pro-active and expert advisory systems. Current efforts to address these needs in a transnational network through co-operation projects between both countries are presented and discussed.

References

Pulido F and Picardo Á (2010) Libro Verde de la Dehesa. Downloable at http://www.accionporladehesa.com

Pinto-Correia T, Ribeiro N, Potes J (2013) Livro Verde dos Montados. Downloable at http://www.icaam.uevora.pt

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Fig 1: Cluster of French words showing terms associated with the tree components of the landscapes, issued from a corpus of 163 official documents.

Agroforestry in the French Green and Blue Corridors policy: towards

promotion of trees?

Guillerme S1*, Takali A1, Canard M1, Labant P1 * Correpondence author: sylvie.guillerme@univ-tlse2.fr

1

Laboraoire GEODE (UMR 5602-CNRS-UTM), 5 allée A. Machado, 31009 Toulouse cedex 9, France

Introduction

In order to stop the biodiversity loss, France launched a national strategy in 2004. It was followed by the Grenelle Environment Forum, in October 2007, to determine policy guidelines for sustainable development. The environmental legal measures were completed by the Green and Blue Corridors (GBC) laws.

This conservation and land planning policy tool is a response to landscape fragmentation and loss of biodiversity 1/ by participating in the preservation, management and rehabilitation of the ecological networks, and 2/ by taking into account human activities - including agriculture - in rural areas.

This became a grid of reading for the environmental policy of the State and territorial collectivities. Agroforestry trees can be at the same time markers of the landscapes and essential components of the ecological corridors. But is GBC really a way to promote agroforestry?

Material

This paper focuses on the analyse of a corpus of 163 French official documents regarding the Green and Blue Corridors implementation at different geographical scales, from national to local levels. Using QDA Miner and Wordstat programs a categorization dictionary has been made out of those documents. Then terms related to agroforestry systems were extracted (fig.1) and analyzed.

Results

France has different traditional agroforestry

systems, such as meadow orchards and wooded meadows, and even trees mixed with vineyards called "hautains". But hedgerows remain the most common traditional landscape structure based on trees outside forests. Modern forms of agroforestry, such as alley cropping are also emerging

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and expanding in the last decade. In the case of the Green & Blue Corridor they all create a real network potential associated with the riparian areas.

Nevertheless agroforestry systems and the tree components remain little mentioned in the official documents in spite of their capacity to provide environmental services in the landscapes, as expected by the GBC. For example the word “tree” (arbre) appears in 56 % of the total number of documents, “hedgerow” (haie) in 68 %, and (bocage) in 42 %. But the word “agroforestry” (agroforesterie) is very little employed, appearing in only less than 10 % of the corpus documents, and with different meanings.

Discussion and conclusions

The implementation of the French Green & Blue Corridor is a complex and long process which can promote agroforestry systems and practices by valuing their potential in terms of eco-systemic services. But this process can also challenge their development at the local level due to the lack of clarity in the definition of the terms used, possibly introducing confusion for the local stakeholders.

References

Bonnin, M. (2006) Les corridors, vecteurs d’un aménagement durable de l’espace favorable à la protection des espèces. Natures Sciences Sociétés 14 : 67-69.

Burel F. (ed.) (1995) Ecological Patterns and Processes in European Agricultural Landscapes. Landscape & urban planning. Volume 31, Issues 1-3 : 1-412.

Cormier L., De Lajartre A.B., Carcaud N. (2010) La planification des trames vertes, du global au local : réalités et limites. Cybergeo : European Journal of Geography, Regional and Urban Planning, Article 504.

Deverre, Christian, Marc Mormont et Christophe Soulard (2002) La question de la nature et ses implications territoriales. In: Perrier-Cornet P. (ed) Repenser les campagnes: 217-237. La Tour-d’Aigues, Éditions de l’Aube, France.

Fabos G.J., Ryan R.L. (2006) Greenway Planning around the World, 2006. Landscape and Urban Planning,Volume 76, Issues 1-4:1-298.

Fortier A. (2009) La conservation de la biodiversité, vers la constitution de nouveaux territoires ? Etudes rurales, 183 : 129-142.

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